Conveyor chains of the type to which the present invention relate, typically comprise a plurality of pivotally interconnected link assemblies, each link assembly comprising a link portion and a so-called top plate portion. As is typical, articles conveyed are supported on the top plate portions. It is known in the prior art to form these link assemblies including the link portion and the top plate portion as an integral molded assembly of polyacetal resin or a resin containing additives such as fluorine and oil. It has been found that these link assemblies have certain disadvantages and drawbacks. For example, link assemblies molded of a polyacetal resin have a high friction factor and thus there is the danger of damage to articles conveyed on the top plate by reason of the sliding motion between the articles. Furthermore, it has been found that the sliding motion produces wear of the polyacetal resin and undesirable formation of powder. Even though link assemblies made of a resin containing fluoride and oil have a low friction factor and good wear resistance, they have the disadvantage of low strength characteristics as compared with link assemblies molded of a polyacetal resin.
It is also known to mount a plate made of a fluorocarbon resin, an ultra-high molecular polyethylene or an elastomer, such as rubber, to the upper surface of the top plate by an adhesive. Even though the plates made of a fluorocarbon resin or an ultra-high molecular polyethylene have a low friction factor, there is the tendency of the resin plate to peel from the top plate portion and thus limit the useful service life of the link assembly. This is also true of plates made of an elastomer such as rubber. Further, the durability thereof is degraded. Moreover, a resin or elastic plate forming a separate element of the top plate portion has a geometric disadvantage in that a stepped portion is formed on the top plate portion by the thickness of the resin or elastic plate hereby tending to catch articles during a conveying cycle.